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31.
[Hg(terpy)2](CF3SO3)2·0.5(CH3)2CO crystallizes in the triclinic space group witha=14.631(6),b=15.258(4),c=18.785(7) Å, =69.66(2), =70.72(1), =88.55(1)°. The crystal structure consists of two independent [Hg(terpy)2]2+ cations, four trifluoromethanesulfonate anions and an acetone molecule in the asymmetric unit. Each mercury atom is coordinated by two tridentate terpyridine ligands forming an irregular six-coordination polyhedron. The Hg–N bond lengths range from 2.27(2) to 2.53(2) Å.  相似文献   
32.
A study on the ductile deformation domain of the brittle fault in the shallow level ofthe crust is a new probe field for the modern structural geology. Taking the southern Jiang-su Province area as an example the orientation measurement of quartz crystals, the com-positional texture observation of three pressure sensitive minerals and the rheological param-eter determination of dislocation densities, etc. have been demonstrated and analysed basedon typical samples in the present paper. In addition, their generation mechanisms arealso discussed from the cataclastic rheology, the dynamic differentiation and the simpleshearing, specially, from the Ode strength theory. Finally, a generative relationship betweenthe ductile deformation domain of the brittle fault system, in the regional layer--slip andthe formation of the stratabound ore deposit is shown as well.  相似文献   
33.
Preparation and Crystal Structure of LnAl3Br12 (Ln = La, Ce, Pr, Nd, Sm, Gd) and Thermal Decomposition to LnBr3 LnAl3Br12 (Ln = La, Ce, Pr, Nd, Sm, Gd) was prepared in crystalline form for the first time. The crystal structures of LaAl3Br12, PrAl3Br12, and NdAl3Br12 were determined on single crystals by X-ray methods. The isotypic compounds crystallize with trigonal symmetry, space group P 3112, Z = 3. A structural comparison to lanthanoide chloroaluminates of equal composition is given and thermal decomposition of LnAl3Br12 (Ln = Nd) to the corresponding lanthanoide tribromide is described.  相似文献   
34.
Combinatorial library of isoxazoles was prepared by 1,3-dipolar cycloaddition on solid support. p-Cyano derivatives showed nematic and/or smectic A phases. A bilayer smectic phase for 2h is proposed by the combination of molecular mechanics calculation and X-ray diffraction experiment.  相似文献   
35.
Substituted 2-aminoindenes have been synthesized in almost quantitative yields by reactions of amines such as methylpiperazine, trimethylethylenediamine, 1,4-diaza-cycloheptane and N,N′-dimethylethylenediamine with 2-indanone. The 2-aminoindenes can be deprotonated and reacted with BrMn(CO)3(Py)2 to produce the respective aminoindenyl-cymantrenes in yields between 55–70%. The X-ray crystal structures of 2-(methylpiperazine)indenyl-cymantrene 5 (P1 , a = 12.667(3) Å, b = 16.630(3) Å, c = 17.382(3) Å, α = 72.70(3)°, β = 74.59(3)°, γ = 88.66(3)°, V = 3364.1(12) Å 3, Z = 8, R1(2σ(I)) = 4.02%, wR2(2σ(I)) = 10.30%) and the HClO4 adduct of 2-(trimethylethylenediamine)-indenyl-cymantrene 6 (Cc, a = 23.722(5) Å, b = 6.9080 Å, c = 13.264 Å, β = 111.77(3)°, V = 2018.6(7) Å 3, Z = 4, R1(2σ(I)) = 2.94%, wR2(2σ(I)) = 7.90%) were determined. In both complexes the indenyl-carbon bonded to nitrogen displays significantly longer bonds to manganese [223.5(3)–225.8(3) pm] than the other four carbon atoms [213.3(3)–219.1(3) pm]. The short indenyl-nitrogen bonds of 136.2(4) and 137.8(4) pm are indicative of a substantial multiple bond character. The complexation of Zn2+ by the nitrogen atoms of 6 results in significant shifts of the CO stretching frequencies.  相似文献   
36.
Wilken  R.  Holländer  A.  Behnisch  J. 《Plasmas and Polymers》2002,7(1):19-39
Using infrared reflection absorption spectroscopy (IRRAS), quartz crystal microbalance (QMB) measurements, and X-ray photoelectron spectroscopy (XPS) in combination with chemical derivatization techniques the VUV photolysis of polyethylene (PE), polypropylene (PP), and polystyrene (PS) was investigated. A mass balance obtained from the quantification of the data was used to suggest reaction path ways. Although PE and PP behave similar, the mass loss is about 8 times higher in the case of PP. These differences originate from the higher disproportionation to recombination ratio for the branched polymer. Both polymers form double bonds and at extended treatment times they tend to crosslink. PS is rather stable due to the possibility of the energy dissipation by fluorescence.  相似文献   
37.
The action of SMe2 on the ten-vertex nido-ruthenaborane [6-(η6-C6Me6)RuB9Hl3] ( 1 ) provides a high-yield route to the unsubstituted isocloso-ruthenaborane [1-(η6-C6Me6)RuB9H9] (2). The benzene analogue [1-(η6-C6Me6)RuB9H9] is prepared similarly. By contrast, reaction of (1) with PhNH2 gives a variety of B-phenylamino isocloso derivatives, including orange crystals of [1-(η6-C6Me6)-2-(PhNH)-isocloso-1-RuB 9 H8] ( 3 ), red-orange [1-(η6-C6Me6)-2,3-(PhNH)2-isocloso-1-RuB9H7] ( 4 ) and dark-red [1-(η6-C6Me6)-5,6,7-(PhNH)3-isocloso-1-RuB9H6] ( 5 ). Detailed 1H and 11B nmr properties of these various compounds are described. The structure of ( 3 ) has been established by a single-crystal X-ray diffraction study of the solvate [1-(η6-C6Me6)-2-(PhNH)-isocloso-1-RuB9H8] · 1/2 CH2Cl2; the crystals were monoclinic, space group C2/c, with a = 1895.1(3), b = 1556.6(3), c = 1716.4(3) pm, β = 104.37(1)° and z = 8.  相似文献   
38.
The reaction of alkali metal hexacyanoferrate(II/III) with (CH2)6N4 (hexamethylenetetramine, abbreviated HMT) in an acidic medium yielded crystalline compounds of stoichiometries HK2[Fe111(CN)6]·2HMT·4H2O, H2K2[Fe11(CN)6]·2HMT·4H2O, and HNa2[Fe111(CN)6]· 2HMT·5H2O. Their crystal structures are based on a packing of three molecular components: neutral and/orprotonated HMT, hexacyanoferrate, and an alkali metal ion-water cluster. The resulting three-dimensional supramolecular framework is constructed from the coordination of the alkali metal ion by aqua ligands as well as [Fe(CN)6]{n–} and HMT units, and further stabilization is achieved by hydrogen bonding between water molecules and the noncoordinated nitrogen atoms of HMT and hexacyanoferrate.  相似文献   
39.
Several non-equilibrium solid solutions belonging to the platinum-osmium systems Os0.9Pt0.1, Os0.8Pt0.2, Os0.5Pt0.5, Os0.7Pt0.3, Os0.75Pt0.25 are prepared and studied. The thermal decomposition of [Pt(NH3)4][OsCl6] in the hydrogen and helium atmosphere is investigated. It is found that the Pt0.5Os0.5 solid solution develops through the formation of (NH4)2[OsCl6] and a metallic phase based on Pt. The crystal structure of a double complex salt [Pt(NH3)4][OsCl6] is studied (X8-APEX Bruker, 1508 independent reflections, R = 2.04%). Crystal data for PtOsN4Cl6H12 are: a = 11.6216(5) Å, b = 11.0016(5) Å, c = 10.3819(5) Å, V = 1327.4(1) Å3, space group Cmca, Z = 4, d x = 3.333 g/cm3. The coordination polyhedron around Os is octahedral: 〈Os-Cl〉 2.357 Å, ∠Cl-Os-Cl 89.5–90.5°, while around Pt it is square-planar: Pt-N 2.046 Å, ∠ N-Pt-N 89.59° and 90.41°.  相似文献   
40.
Crystal structures of two new misfit compounds, [SrGd0.5S1.5]1.16NbS2 and [Sr(Fe,Nb)0.5S1.5]1.13NbS2, were determined through the composite approach, i.e., by refining each subpart (Q, H-parts, and the common part) of these composite materials, separately. The Q-part is a three-atom-thick layer, with the NaCl-type structure, where external SrS planes enclose the inner GdS or (Fe,Nb)S plane; the structural difference between these two compounds lies in the central layer within the Q-part: Gd and S atoms are in special positions (octahedral coordination), while Fe and S atoms are statistically distributed on split (×4) positions (tetrahedral coordination) around a central unique site (=special position occupied by Nb). The H-part is a sandwich of sulfur planes enclosing the inner Nb plane as observed for the structure of the binary compound NbS2 itself. The Sr-Gd derivative shows a paramagnetic behavior in the whole studied temperature range (2-300 K). On the other hand, antiferromagnetic interactions occur in the Sr-Fe derivative; the complex magnetic behavior of this compound is related to the statistical distribution of Fe atoms which leads to frustration of the magnetic interactions. At room temperature, experimental values obtained from Mössbauer spectrum correspond to Fe3+ in tetrahedral sulfur environment: isomer shift δ=0.32 mm s−1, and quadrupole splitting ΔE=0.48 mm s−1.  相似文献   
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